A system for assembling a building lumber package includes a lumber sorter sequentially receiving a plurality of boards of different dimensions and selectively placing boards into a plurality of bins, a computer programmed to receive a list of different dimension lumber, to designate one or more bins for accumulating the lumber designated on the list, to receive dimension information identifying each board received by the sorter, and to control the lumber sorter to place boards designated on the list into bins designated for accumulating lumber identified on the list The system may process a plurality of orders for building lumber packages at essentially the same time. Lumber at a lumber mill is sorted into building lumber packages at the lumber mill and stacked and strapped by automated stackers and strappers at the lumber mill. The building lumber packages may be shipped directly from the lumber mill to a building site.